Many of the current squad have signed up to add their backing at ambassadorial level for each of the four charities and are looking forward to showing their support over the course of the coming season.
Commenting on the launch of Leinster's charity activity this year, Leinster captain Leo Cullen said: "The Leinster squad are delighted to lend our support to four outstanding charities - Action Breast Cancer, the Irish Heart Foundation, Temple Street Children's Hospital and Welcome Home - for the 2009/10 season.
"We are pleased to continue our relationships with ABC, who run campaigns throughout the year for those affected by breast cancer and events like 'Ladies Night' around our St. Valentine's Day fixture has become an important awareness fundraiser during the Leinster calendar.
"Equally, Fr. Peter McVerry's work in the community is hugely important for those who are isolated and on the fringes of society.
"This year we are delighted to welcome both the Irish Heart Foundation who raise awareness for heart health and help patients manage diseases like strokes, and Temple Street Children's Hospital who do so much to help children across Ireland every day.
"A huge number of the squad will be adding their support to the various appeals throughout the season and we hope that we will be able to bring some good to the local and national communities.
"I would like to thank all supporters who have contributed so far and appeal to you all to help in any way you can, however large or small, to these great charities."
In addition to the official charities of Leinster Rugby, numerous other existing charities, hospitals and community projects will continue to benefit from the support of Leinster players on a personal capacity.
Naomi Fitzgibbon, Cancer Information Service Manager, said: "All women in Ireland need to be breast aware and women living in Ireland are becoming more breast aware which is really encouraging.
"At Action Breast Cancer we are now focusing our energies into making all women aware of the risk factors for developing breast cancer.
"Our relationship with Leinster Rugby allows us to promote these important messages, and raise all-important funds, in the drive to inform women."
Michael O'Shea, Chief Executive of the Irish Heart Foundation, said: "At the Irish Heart Foundation we are delighted to be chosen as one of the charities supported by Leinster Rugby for the 2009/2010 season.
"Promoting physical activity and healthy lifestyle is at the heart of our work in preventing cardiovascular disease which is the biggest cause of death in our country.
"Our charity is proud to be associated with Leinster Rugby, the European champions whose players are excellent ambassadors not only for their province and country but also as healthy role models to our young people. We look forward to an energetic and fruitful partnership."
Denise Fitzgerald, CEO, The Fundraising Office, Temple Street, added: "We are delighted that Temple Street has been chosen as a charity partner for Leinster Rugby for the coming year.
"Like Leinster Rugby, we have an amazing team here in Temple Street Children's University Hospital with fantastic supporters.
"The support that we continue to receive from both the Leinster players and the management team is greatly appreciated by the children, parents and staff at the hospital and we look forward to what looks set to be a very exciting partnership."
Fr. Peter McVerry commented: "My thanks go to Leinster Rugby for their continued support for Welcome Home Charity.
"Welcome Home has been raising money since 1990 to support the work of the Peter McVerry Trust with young, homeless people in Dublin.
"Without Welcome Home, the accommodation, support services, drug detox centre and aftercare houses would not be in existence today as we would not have survived in the early days without the funds donated by Welcome Home.
"More recently, Leinster Rugby has been a supporter of Welcome Home and has provided a number of opportunities for Welcome Home to raise money.
"It has also given Welcome Home an opportunity for increased awareness among Leinster's supporters. On behalf of those who will benefit from any increased funds generated by this gesture, my sincere thanks."